package com.gl.emms.whale.util;

import java.security.MessageDigest;

public class MD5 {

	private MD5() {}

	public final static String getMessageDigest(byte[] buffer) {
		char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
		try {
			MessageDigest mdTemp = MessageDigest.getInstance("MD5");
			mdTemp.update(buffer);
			byte[] md = mdTemp.digest();
			int j = md.length;
			char str[] = new char[j * 2];
			int k = 0;
			for (int i = 0; i < j; i++) {
				byte byte0 = md[i];
				str[k++] = hexDigits[byte0 >>> 4 & 0xf];
				str[k++] = hexDigits[byte0 & 0xf];
			}
			return new String(str);
		} catch (Exception e) {
			return null;
		}
	}
	//MD5加密，32位    
	public static String getMD5(String str){
		MessageDigest md5 = null;    
		try{    
			md5 = MessageDigest.getInstance("MD5");    
		}catch(Exception e){    
			e.printStackTrace();    
			return "";    
		}    
		char[] charArray = str.toCharArray();    
		byte[] byteArray = new byte[charArray.length];    
		for(int i = 0; i <charArray.length; i++){    
			byteArray[i] = (byte)charArray[i];    
		}    
		byte[] md5Bytes = md5.digest(byteArray);    
		StringBuffer hexValue = new StringBuffer();    
		for( int i = 0; i <md5Bytes.length; i++)    
		{    
			int val = ((int)md5Bytes[i])&0xff;    
			if(val <16)    
			{    
				hexValue.append("0");    
			}    
			hexValue.append(Integer.toHexString(val));    
		}    
		return hexValue.toString();    
	} 
}
